1. Field of the Invention
The present invention relates to an insertion apparatus for generating a propulsion power to introduce an insertion portion into an examinee's body.
2. Description of the Related Art
Recently, an endoscope equipped with an elongated insertion portion having flexibility has been utilized in inspection, treatment, or the like in the medical field. With the endoscope, not only observation of an intracavital organ and the like may be performed without incision by inserting the insertion portion into an intracavital region, but also a variety of therapies and treatments may be performed by introducing an accessory into an intracavital region through a treatment device insertion channel provided in the insertion portion as needed. In the endoscope, a bending section is provided at the distal side of the insertion portion. The bending section can be made to bend in, for example, up and down directions, left and right directions, or the like by performing forward/backward movements of a manipulation wire connected with bending parts constituting the bending section. The manipulation wire is to be moved forward/backward by rotating manipulation of, for example, a bending knob provided at a manipulation section.
When performing endoscopy, the insertion portion must be inserted into an intricately structured intracavital region. When the insertion portion is inserted into a intricately structured lumer, for example, a colon or the like which describes 360 degree loop, an operator manipulates the bending knob to bend the bending section, and performs hand manipulation such as twist manipulation of the insertion portion to move the distal end of the insertion portion toward a target portion to be observed.
However, a skill is required to be able to introduce the insertion portion to the deepest part of the intricately structured colon smoothly in a short time without giving pain to a patient. In other words, there exists a risk that loss of the intended insertion direction may occur when inserting the insertion portion into a deep portion, and a change in shape of the intestine may be caused when inserting the insertion portion into a deep portion of the intestine. Accordingly, various proposals for improving insertability of the insertion portion have been made.
There is disclosed a propulsion device for a medical device which enables easy introduction of the medical device into a deep portion of a live body duct with low invasiblity, for example, in Japanese Patent Application Laid-Open Publication No. H10-113396. In the propulsion device, a rib declining relative to the axial direction of a rotating member is provided at the rotating member. Accordingly, rotating power of the rotating member is converted to propulsion power by the rib by rotation of the rotating member and the medical device connected to the propulsion device is moved in a direction toward the deep portion by the propulsion power.